September 3 marks the 190th anniversary of the Hurricane of 1821, which saw flooding and destruction in the growing metropolis. In less than an hour a thirteen-foot storm surge deluged the city, swallowing everything below Canal Street. The Battery was particularly devastated, docks were destroyed, and ships were swept onto streets. Further uptown, a bridge that connected Harlem to Ward’s Island was washed away and somewhere in Chinatown, the East River likely met the Hudson. “New Yorkers were lucky,” writes Bruce Parker in The Power of the Sea: Tsunamis, Storm Surges, Rogue Waves, and Our Quest to Predict Disasters. “The hurricane hit at low tide.“

By the time Hurricane Sandy veered toward the Northeast coast of the United States last October 29, it had mauled several countries in the Caribbean and left dozens dead. Faced with the largest storm ever spawned over the Atlantic, New York and other cities ordered mandatory evacuations of low-lying areas. Not everyone complied. Those who chose to ride out Sandy got a preview of the future, in which a warmer world will lead to inexorably rising seas.

The largest Atlantic storm ever? Where do they find people to write garbage like that? How big was the 1780 Great Atlantic hurricane which killed 23,000 people? Hurricane Andrew had wind speeds 300% of Sandy.

Sandy’s flooding was a storm surge, not sea level rise. Where do they find people to write garbage like that?

Sea level has been rising for 20,000 years. Most of that time the Earth has been…